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Another head gasket thread

Discussion in 'Gen 3 Prius Technical Discussion' started by VTPrius419, Nov 17, 2022.

  1. VTPrius419

    VTPrius419 Junior Member

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    Ok yet another head gasket thread! Couple things I am hoping for some advice on. First I am 97% sure the gasket is gone. Checked all the basics found one spark plug very dirty with deposits not even sure how/if it was firing. This was the second plug from the passenger side when standing in the front of the car. At that time I cleaned the plug put it all back together and had the same issue. Pulling coil wires while running made the same knock shake issue so I replaced all the coils. No luck there. Final act was to run the car without the radiator cap. Works for now so I would think thats 100% head gasket territory. Anyways I guess the question is how long does anyone think I can get away driving like this? I plan to do the job but don't have a garage and would need to drive a few hours away where there is one I can use for a few days. Also for info's sake I have done the EGR about 20k ago the motor burns no oil and has no water/antifreeze in the oil at all.

    On a side note I think the gasket has been going for years just slowly and here is why maybe someone can agree or not? Quite often for years there has always been this small knock like sound when driving when it goes from elec to engine running. It has been slight and I had thought maybe something was worn in the trans giving it a bit of slop. Well today when driving without the radiator cap it was smooth as glass the clink was gone. That leads me to think it was leaking a small bit for a while now.

    Thanks for any advice here!
     
  2. Tombukt2

    Tombukt2 Senior Member

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    So before you get ready to do the head gasket you want to look on your engines backside halfway up the motor to the centerpiece and make sure you don't see any stress marks along that center girdle and if you do then don't do the head gasket maybe just get a replacement engine a JDM replacement will cost you about what you're going to put out in the head gasket think hard before you do this an open deck engine design is inherently weak or weaker so you may want to reconsider or maybe not I wouldn't work on the open deck unless I was buying new sections or what have you a short block if you will and that's quite expensive if you think you're going to have the car through the return on that investment maybe think again but anyway good luck.
     
  3. VTPrius419

    VTPrius419 Junior Member

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    Well I am doing the work myself so cost is just my time and most likely a new motor is way out of the budget plus this one ran great and used zero oil. Could you explain a bit more or maybe a link with a photo of where to look for these marks? And what would they be small cracks on the metal or something like that?